Russia's Sports Minister says a stadium being built in the city of St. Petersburg for the 2018 World Cup has suffered further delays.

Vitaly Mutko tells state news agencies that the 69,000-seat arena, which will host a World Cup semifinal, is now three months behind schedule.

Mutko linked the delay to financial concerns involving contractorst.

The end of construction had previously been set for May, with the stadium due to enter service by the end of the year.

It is not the first delay for the stadium. Work on the site started in 2006, and the arena was once planned to open in 2008 before it was hit by frequent delays, cost rises, design changes and accusations of mismanagement.